I don't like Razer headsets at all. They feel cheap and I was not impressed with the sound in any way. My local Best Buy has Kraken Pro's and G430's on display and I got to wear and listen to them both.
The Razer headset felt cheap and uncomfortable with ear cups shaped like perfect circles. While it didn't sound BAD, there was nothing that I felt was great either.
As far as the G430's go, I was pretty happy with them. They sounded pretty good and were far more comfortable than the Kraken Pro. While they don't sound as good as something like my PC360's, nor are as durable and comfortable as my PC360's, but they don't feel cheap like the Kraken Pro does.
It is my understanding, but I could be wrong, that Logitech uses the same drivers...